Detecting agent

Abstract

A detecting agent for detecting at least one member selected from the group consisting of halogen gases and acidic gases which is contained in a gas, wherein the detecting agent comprises a discoloring component which comprises a hydroxide of a transition metal and Congo Red. Halogen gases and acidic gases which are contained in hydrogen, nitrogen, argon, or helium can be detected under a dry condition with a high sensitivity in accordance with the present invention.

What is claimed is: 
     
       1. A detecting agent for detecting at least one member selected from the group consisting of halogen gases and acidic gases which is contained in a gas, wherein the detecting agent comprises a discoloring component which comprises a hydroxide of a transition metal and Congo Red. 
     
     
       2. A detecting agent according to claim 1, wherein the transition metal is at least one metal selected from the group consisting of nickel (II), cobalt (II), and manganese (II). 
     
     
       3. A detecting agent according to claim 1, wherein the ratio by weight of the hydroxide of a transition metal to Congo Red is in a range of 1:(0.01 to 0.00001). 
     
     
       4. A detecting agent according to claim 1, wherein the halogen gases are selected from the group consisting of fluorine gas, chlorine gas, bromine gas, chlorine fluoride gas, and chlorine trifluoride gas. 
     
     
       5. A detecting agent according to any of claim 1, wherein the acidic gases are selected from the group consisting of hydrogen fluoride, tungsten hexafluoride, silicon tetrafluoride, boron trifluoride, hydrogen chloride, silicon tetrachloride, and boron trichloride. 
     
     
       6. A detecting agent according to claim 1, wherein the hydroxide of a transition metal and Congo Red are supported on an inorganic support. 
     
     
       7. A detecting agent according to claim 6, wherein the hydroxide of a transition metal is cobalt (II) hydroxide and the inorganic support is silica gel. 
     
     
       8. A detecting agent according to claim 6, wherein the inorganic support is at least one member selected from the group consisting of silica gel, silica-alumina, titania, alumina, and zirconia. 
     
     
       9. A detecting agent according to claim 6, wherein the ratio by weight of the support to the hydroxide of a transition metal and Congo Red is in a range of 1:(0.15 to 0.0001):(0.1 to 0.00001). 
     
     
       10. A detecting agent according to claim 7, wherein the ratio by weight of the support to the hydroxide of a transition metal and Congo Red is in a range of 1:(0.15 to 0.0001):(0.1 to 0.00001). 
     
     
       11. A detecting agent according to claim 8, wherein the ratio by weight of the support to the hydroxide of a transition metal and Congo Red is in a range of 1:(0.15 to 0.0001):(0.1 to 0.00001). 
     
     
       12. A detecting agent according to claim 2, wherein the hydroxide of a transition metal and the Congo Red are supported on an inorganic support and the ratio by weight of the support to the hydroxide of a transition metal and Congo Red is in a range of 1:(0.15 to 0.0001):(0.1 to 0.00001). 
     
     
       13. A detecting agent according to claim 9, wherein the ratio by weight of the support to the hydroxide of the transition metal and to the Congo Red is 1:(0.05 to 0.005):(0.01 to 0.0001). 
     
     
       14. A detecting agent according to claim 10, wherein the ratio by weight of the support to the hydroxide of the transition metal and to the Congo Red is 1:(0.05 to 0.005):(0.01 to 0.0001). 
     
     
       15. A detecting agent according to claim 11, wherein the ratio by weight of the support to the hydroxide of the transition metal and to the Congo Red is 1:(0.05 to 0.005):(0.01 to 0.0001). 
     
     
       16. A detecting agent according to claim 12, wherein the ratio by weight of the support to the hydroxide of the transition metal and to the Congo Red is 1:(0.05 to 0.005):(0.01 to 0.0001).